The ESB has raised €500m by selling a seven year bond today.
The company will pay investors an interest rate of just under 4.5%.
The money will be used to fund the organisation's capital expenditure and to pay off existing debt.
Semi-state organisations, which raise money on the bond market, had been affected by Ireland's sovereign debt crisis which saw Government bonds downgraded by ratings agencies.
However, Ireland's eight year benchmark Irish bond is trading with an interest rate of 4.78%, significantly down from a peak of 15% in the middle of 2011.
The ESB is taking advantage of stronger demand for its bonds by tapping the markets.
Bond sale was oversubscribed by 12 times
In a statement, ESB said the bonds were being bought mainly by European institutional investors and the total amount of orders received was over €6 billion.
It follows ESB's successful €600m 5 year issuance in September.
The longer tenor and lower yield of today's deal reflects improving market sentiment towards ESB and Irish bonds generally, the ESB said.
The company has a target of €280m in annual cost reductions between 2010 and 2015, which equates to an overall reduction of 25%. Staff numbers have fallen from 7,836 in 2008 to 6,827 last year.
